If galvanized pipes are to be protected against corrosion, what kind of paint and coatings should be used?
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Our company’s torch towers are currently coated using the hot-dip galvanizing process, and we are concerned about their short lifespan; therefore, we plan to apply an anti-corrosive coating on top of the galvanized layer. What kind of paint and coatings should be used?
Have heard of those that use epoxy resin and polyurethane
There are also those coated with silver powder or fluorocarbon paint; I’ve only heard about them though, and I’m not sure what the results are
It is recommended that you avoid using paint; its lifespan is certainly not as good as that of hot-dip galvanizing. If you are concerned, you can specify the thickness of the zinc layer in the hot-dip galvanizing process. If the paint starts to peel off after 3 years, will you repair it or not? It’s best to check the tower during the major repair, and apply additional paint to those areas where the hot-dip zinc coating is poor.
It is recommended to purchase ready-made corrosion-resistant pipes, with galvanized pipes coated with epoxy powder or polyurethane that provides UV resistance. Research findings from the American Galvanizing Institute show that galvanized pipes can have their corrosion resistance lifespan extended by 1.5 to 2 times.
Anticorrosion coatings and the polyurethane series have all been taken into consideration
Increasing the thickness of the zinc layer is a reliable approach; hot-dip galvanizing will hold up for thirty to fifty years without problems. Painting it seems pointless.
It’s already galvanized, so why apply paint? Galvanizing provides far better corrosion protection than painting!
Use epoxy just for practicality, without focusing on aesthetics
Applying paint after hot-dip galvanizing is actually an incorrect approach, as painting requires surface preparation. If surface treatment is carried out on a hot-dip galvanized surface, it will damage the existing galvanized layer; whereas if no surface treatment is done, applying paint is simply a waste of effort. If safety is a concern, one can increase the safety margin and the corrosion margin during the design process.